The daily supplemental dosage is 500 to 1,000 milligrams. You can divide the amount into a few doses per day. Start with a smaller dosage the first time you start taking the extract and gradually increase the dosage as your body allows. Taking olive leaf extract may help with the following:

Olive leaf extract comes from the leaves of an olive plant. It contains an active ingredient called oleuropein. This nutrient is thought to contribute to the anti-inflammatory and antioxidant properties of olive leaf extract.

You may have heard how a Mediterranean diet has been linked to a decrease in chronic diseases, especially cardiovascular disease. This is thought to be due to the focus on olive oil, leaves, and fruit in the diet. It’s been used as traditional medicine for centuries in countries like Greece, Morocco, and Tunisia.

Here’s what research says about the biggest reported benefits of olive leaf extract.

Treats herpes

To treat herpes with olive leaf extract, drop 1 to 2 droplets on a cotton ball and place on the sore. One study found that olive leaf extract’s antiviral and antimicrobial factors reduce the ability of the herpes virus to invade surrounding cells.

Protects the brain against Alzheimer’s and Parkinson’s

Oleuropein is also shown to have a protection against Alzheimer’s disease. The antioxidant effects of olive leaf extract may also help with preventing damage or loss of dopamine neurons that’s associated with Parkinson’s disease as well.

Improves heart health

Researchers believe olive leaf extract can have positive effects on atherosclerosis, or narrowing of the arteries, which is the highest risk factor for heart disease. High levels of LDL, or “bad” cholesterol, and total cholesterol are risk factors for developing this disease. One animal study from 2015 assessed the effects of olive leaf extract on cholesterol levels. Rats who took the extract for eight weeks had significantly decreased cholesterol levels.

reduce blood glucose, plasma malondialdehyde, and other signs of oxidative stress (an imbalance of free radicals that can harm the body)

reduce cholesterol

decrease serum glucose

increase serum insulin

However, more studies testing olive leaf extract on humans are needed. One human study found that people who took olive leaf extract tablets lowered their average blood sugar level and fasting plasma insulin levels. However, insulin levels after eating weren’t significantly affected.

Supports weight management

Along with heart-healthy benefits and type 2 diabetes protection, it makes sense that olive leaf extract could also help with weight loss. An animal study from 2014 researched the effect of olive leaf extract in preventing high-fat, diet-induced obesity. It’s thought that olive leaf extract prevents obesity by regulating the expression of genes that affect weight gain. It can also aid in reducing food intake.

Reduces cancer risk

In one cell study, olive leaf extracts were shown to stop cancerous cell growth. Researchers suggest that the extract has strong antioxidant properties, but this is also one of the first studies on olive leaf extracts and their anticancer effects. More research is needed to prove this benefit.

Talk to your doctor before trying olive leaf extract. Remember that some changes may be subtle and gradual over time. You may also not experience any changes at all with olive leaf extract. This isn’t a cure-all supplement, but it may help with your goals for weight loss, improved health, and boosted immunity.